Table 1.
The clinical characters of the patients.
| Clinical characteristics | Total (n=401) | clinical pregnancy (n=204) | Non-clinical pregnancy (n=197) | P |
|---|---|---|---|---|
| Age (year), mean ± s.d. | 31.7 ± 5.3 | 30.7 ± 4.8 | 32.7 ± 5.6 | 0.0002 |
| BMI (kg/m2), mean ± s.d. | 22.6 ± 3.0 | 22.7 ± 3.4 | 22.4 ± 2.6 | 0.37 |
| Type of infertility, n (%) | 0.01 | |||
| Primary | 205 (51.1) | 117 (57.4) | 88 (44.7) | |
| Secondary | 196 (48.9) | 87 (42.7) | 109 (55.3) | |
| Endometrial preparation protocol, n (%) | 0.19 | |||
| GnRH-a-HRT | 116 (28.9) | 65 (31.9) | 51 (25.9) | |
| HRT | 285 (71.1) | 139 (68.1) | 146 (74.1) | |
| Number of transferred embryos, n (%) | 0.47 | |||
| 1 | 184 (45.9) | 90 (44.1) | 94 (47.7) | |
| 2 | 217 (54.1) | 114 (55.9) | 103 (52.3) | |
| Number of good quality embryos per transferred cycle, n (%) | 0.0008 | |||
| 0 | 35 (8.7) | 8 (3.9) | 27 (13.7) | |
| 1 | 199 (49.6) | 100 (49.0) | 100 (50.8) | |
| 2 | 167 (41.7) | 96 (47.1) | 70 (36.5) | |
| good-quality embryo rate (%) | 87.8 ± 0.3 | 93.4 ± 0.2 | 82.0 ± 0.4 | 0.0001 |
| Types of embryos transferred, n (%) | 0.64 | |||
| Cleavage embryos | 190 (47.4) | 99 (48.5) | 91 (46.2) | |
| Blastocysts | 211 (52.6) | 105 (51.5) | 106 (53.8) | |
| Serum estradiol level on the day of embryo transfer (pg/ml), mean ± s.d. | 434.8 ± 444.5 | 393.9 ± 385.6 | 477.1 ± 495.6 | 0.12 |
| Serum progesterone level on the day of embryo transfer (ng/ml), mean ± s.d. | 15.8 ± 7.6 | 15.8 ± 7.4 | 15.8 ± 7.8 | 0.95 |
| Endometrial thickness (mm), mean ± s.d. | 9.3 ± 1.7 | 9.5 ± 1.7 | 9.0 ± 1.6 | 0.001 |
| Endometrial morphology, n (%) | 0.47 | |||
| Type A | 345 (86.0) | 178 (87.3) | 167 (84.8) | |
| Type B | 56 (14.0) | 26 (12.8) | 30 (15.2) |
Categorical variables were described as frequencies (percentages), and continuous variables were described as the mean ± standard deviation (SD). Pearson’s chi-square test and Student’s t-test were used for parametric comparisons. P value < 0.05 was considered to indicate statistical significance.
BMI represents body mass index; GnRH-a-HRT represents gonadotropin releasing hormone agonist down-regulation in combination with hormone replacement therapy; HRT represents conventional hormone replacement therapy.